KR20210099392A - Method for Split Injection Control on Cold Start and Engine System Thereof - Google Patents

Abstract

A method for split injection control on cold start that is applied to an engine system (1) allows a split injection controller (2) to: perform cold-start split injection with three split injection operations of an injectors (1-2) in accordance with the cold start operation of the engine system (1) to measure, an operating value, at least one among an injector opening angle, an injector operating time, and an injector operation frequency; read, as a verification value, at least one among a target injector opening angle, a target injector closing angle, a target injector operating time, and a target injector operation frequency; and apply the read verification value to a failure determination on the cold-start split injection. Therefore, the method satisfies both CARB OBD-2 section 1968.2 that has stipulated three fuel injection operations and North American AECD document requirements that has stipulated cold-start control failure diagnosis, and in particular, can preemptively respond to the strengthening of emission gas regulations by expanding the cold-start area by the split injection control. The method comprises an injection mode control step and an injection failure diagnostic control step.

Description

Method for Split Injection Control on Cold Start and Engine System Thereof

The present invention relates to a cold-start split injection control, and in particular, a split-injection control that is effective for reducing exhaust gas under cold-start operation conditions is realized by performing fault diagnosis for each injector operation of three split injections applied in a triple injection pattern during cold start. It's about the engine system.

In general, ignition timing control, fuel quantity control, CVVT (Continuously Variable Valve Timing) control, etc. are applied to the engine, thereby contributing to reducing cold start exhaust gas generated from the vehicle.

In particular, the split injection control at the time of starting the engine for two or more times contributes to improving the combustion stability and emission reduction performance of the engine.

Furthermore, the split injection control during cold start is being adopted as a response strategy to strengthen the emission gas regulation of vehicles by extending the effects of combustion stability and emission reduction of the engine to the cold starting area of the engine, which was not previously applied.

Domestic Patent Publication No. 10-1994-0011775 (1994.06.22)

However, in order for the split injection control to be newly applied to the vehicle during cold start, in the North American regulations of the North American laws, CARB OBD-2 section 1968.2, “Regulations on fault diagnosis for the control used during cold start” and the North American AECD documents for the injection mode during cold start. It must meet the “Regulation for Homogeneous Injection (Triple)”. In this case, the AECD means an auxiliary emission control device.

Therefore, in order for the split injection control to be applied to the vehicle during cold start, it is necessary to be able to diagnose a malfunction of the cold start control and satisfy the requirement of three or more split injections in the injection mode.

Accordingly, the present invention in consideration of the above points satisfies the injection mode regulation with the split injection control implemented with a triple injection pattern during cold start of the engine, and the number of divided injections, the injection time and the injection angle measured from the triple injection pattern is used to determine the failure diagnosis The purpose is to provide a cold-start split injection control method and engine system that can meet the breakdown diagnosis regulations for cold-start control by performing this, and can respond to the strengthening of emission gas regulations by expanding the cold-start range of the split injection control.

In order to achieve the above object, the cold start split injection control method of the present invention includes an injector mode control step of performing cold start split injection by the operation of an injector by a split injection controller that determines a cold start condition of an engine system, and an injector It characterized in that it includes an injection failure diagnosis control step of performing an injection failure diagnosis using any one or more of the injector opening angle, the injector operating time, and the number of injector operation measured through fuel injection.

As a preferred embodiment, the cold start condition is a coolant temperature applied as a determination condition with a set coolant temperature of 56° C., and an engine rotation applied as a determination condition with a set engine speed range of 700 to 960 RPM (Revolution Per Minute). number, and after considering the coolant temperature first, the cold start condition is determined in consideration of the engine speed.

As a preferred embodiment, the injectsen mode control performs the cold start split injection to generate any one or more of an injector opening angle, an injector closing angle, an injector operation time, and the number of injector operation as an injector operation detection value.

As a preferred embodiment, the injector mode control includes the steps of determining the operating current inflection point by detecting the injector operating current according to the start of fuel injection, measuring the injector opening time and measuring the injector opening angle, and injector operation according to the start of fuel injection The operation voltage inflection point is determined by voltage detection, the injector closing time and the injector closing angle are measured according to the end of fuel injection, the injector operating time is calculated, and the number of injector operations is counted.

In a preferred embodiment, the injector operating time is calculated as the difference between the closing time of the injector and the opening time of the injector.

As a preferred embodiment, the injecten mode control is performed in a first injecten mode, a second injecten mode, and a third injecten mode in which the number of injector operation is increased by one count.

As a preferred embodiment, the injection failure diagnosis control includes: checking a target injector opening angle, a target injector closing angle, a target injector operating time, and a target injector operating time; A step of making a time verification determination for , the step of making an angle verification determination for the injector opening angle with the injector opening angle and the target injector opening angle, Checking the number of times for the number of injector operation with the target injector operation number This is carried out in steps.

As a preferred embodiment, a time index calculation value obtained by dividing the difference between the target injector operating time and the injector operating time by the target injector operating time and a time index threshold are applied to the time verification determination, and the time index threshold is When the time index calculation value is less than the time index threshold value as 0.2, the cold start split injection is determined to be faulty.

As a preferred embodiment, the angle index calculation value obtained by dividing the difference between the target injector opening angle and the injector opening angle by the target injector opening angle and the angle index threshold are applied to the angle verification determination, and the angle index threshold is When the calculated value of the angle index is less than the threshold value of the angle index by 0.2, the cold start split injection is determined to be faulty.

As a preferred embodiment, the number check applies 3 to the target injector operation frequency and the injector operation frequency, and when the target injector operation frequency and the injector operation frequency are not 3, the cold-start split injection is determined as a failure .

In addition, the engine system of the present invention for achieving the above object performs cold-start split injection with three divided injection operations of the injector according to the cold-start operation to achieve any one or more of the injector opening angle, the injector operating time, and the number of injector operations. is an operating value, and any one or more of the target injector opening angle, target injector closing angle, target injector operating time, and target injector operation count is read as a verification value and applied to the failure determination for the cold start divided injection. An engine warning light for warning of the failure determination by the control of a controller and the divided injection controller is included.

In a preferred embodiment, the divided injection controller determines the condition of the cold start operation as one or more of a set coolant temperature applied to the coolant temperature and a set engine speed range applied to the engine speed.

In a preferred embodiment, the divided injection controller includes an injector open determination unit that detects an operating current inflection point of the injector, an injector close determination unit that detects an operating voltage inflection point of the injector, an injector operation detection unit that generates the operating value, and the verification The operation value and the verification value are applied to any one of an injector operation target unit that generates a value, a time verification determination for the injector operating time, an angle verification determination for the injector opening angle, and a number verification for the number of operation of the injector It is composed of a cold start division injection determination unit that performs the failure determination and a failure determination unit that outputs a signal for the failure determination.

The cold start split injection control implemented in the engine system of the present invention implements the following actions and effects.

First, by extending the split injection control to the engine cold-start area, it is possible to further improve the effect of reducing emission gas as well as responding to stricter emission gas regulations. Second, the split injection control performs three or more divided injections in parallel with normal operation diagnosis for each in a triple injection pattern, thereby satisfying North American laws and North American AECD documents. Third, by using the number of divided injections, injection time, and injection angle measured from the triple injection pattern as failure diagnosis variables, the failure diagnosis decision logic can be implemented simply. Fourth, the synergistic effect of ignition timing control, fuel amount control, CVVT control, split injection control at startup, and split injection control at cold start improves the engine's combustion stability and exhaust gas reduction performance, thereby greatly improving vehicle marketability.

1 is a flowchart of a cold-start split injection control method according to the present invention, FIG. 2 is a diagram of an engine system in which a cold-start split injection control according to the present invention is implemented, and FIG. 3 is an injector of a split injection controller according to the present invention It is an example of an injection injection diagram for determination of open/close, injection start angle, and number of injections. 6 is a flowchart in which the first injecten mode, which is the first number of times of mode control, is executed, and FIG. 6 is a flowchart in which the second injecten mode, which is the second number of times of the injecten mode control according to the present invention, is executed, and FIG. 7 is a flowchart of the present invention It is a flowchart in which the first injecten mode, which is the third number of injecten mode control according to , is executed.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying illustrative drawings, and since such an embodiment may be implemented in various different forms by those of ordinary skill in the art to which the present invention pertains as an example, it will be described herein It is not limited to the embodiment.

Referring to FIG. 1 , the cold start split injection control method enters the cold start split injection control (S20) through the cold start determination control (S10) in which the engine coolant temperature and engine rotation speed are applied as cold start determination variables, and enters the injectsen mode. 3 times fuel injection (or 3 times homogeneous injection (Triple)) by control (S30) and cold start control fault diagnosis by injection failure diagnosis control (S40) By satisfying the diagnosis of failures in North American AECD documents and CARB OBD -2 ensure that the provisions of section 1968.2 are met.

As a result, the cold-start split injection control method is the injection signal voltage and current measured for each of the injection patterns using the divided injection number of three or more when the cold-start split injection is performed. Whether or not the set standard is satisfied is monitored, and the occurrence of two or more failures can be notified with an engine warning light.

Therefore, the cold-start split injection control method is a cold-start split injection pattern, and it is possible to determine a failure diagnosis by measuring the number of split injections, injection time, and injection angle. It is characterized as a cold-start split injection control method for

Referring to FIG. 2 , an engine system 1 of a vehicle includes an engine 1-1, a plurality of injectors 1-2 installed in a cylinder 1-1A of the engine 1-1, and a fuel rail 1- 3), a high-pressure pump (1-4), a fuel rail pressure sensor (1-5), an engine warning light (1-6), and a split injection controller (2).

Specifically, the engine system 1 is a GDI (Gasoline Direct Injection) engine system that supplies fuel directly injected into a combustion chamber to a low-pressure pump and a high-pressure pump.

For example, the injector 1-2 injects fuel into the cylinder 1-1A (eg, 4-cylinder) of the engine 1-1 using a high-pressure pump and a low-pressure pump, and the fuel rail 1-3 is A high-pressure fuel transport path is formed, and the high-pressure fuel pump (1-4) is linked with a cam knob when the pump driving cam is rotated to form a high pressure rail pressure leading to the injector (1-2), and the fuel rail The pressure sensor 1-5 detects the fuel injection pressure, and the engine warning light 1-6 is provided on the cluster of the driver's seat to inform the driver of the split injection failure of the engine 1-2. Therefore, the engine 1-1, the injector 1-2, the fuel rail 1-3, the high-pressure pump 1-4, the fuel rail pressure sensor 1-5 and the engine warning light 1-6 are It is a common component.

Specifically, the split injection controller 2 outputs a pumping pulse and a flow control valve (FCV) driving pulse of the high-pressure fuel pump 1-4, and controls the driving current and voltage of the injector 1-2, and Equipped with a memory loaded with a program or algorithm for the injection detection control (S30)/injection failure diagnosis control (S40)/failure determination (S50) of the start determination control (S10) and the cold start split injection control (S20), the program Alternatively, it operates as a Central Processing Unit that implements the logic processing of the algorithm.

In addition, the split injection controller 2 is connected to the engine ECU (Electronic Control Unit) 10 and CAN (Controller Area Network), and the engine information detected by the engine controller 10 is the coolant temperature and engine rotation speed (eg, RPM: Revolution Per Minute) is read as input data.

In particular, the divided injection controller 2 includes an injector operation measurement unit 3, an injector operation detection unit 4, an injector operation target unit 5, a cold start division injection determination unit 6, and a failure determination unit, as shown in FIG. 7), and the operation of each of these components will be described in detail along with the step-by-step procedure of the cold start split injection control (S20).

Hereinafter, a method of extending the static flow rate learning section using the injector closing detection time of FIG. 1 will be described in detail with reference to FIGS. 2 to 6 . In this case, the control subject is the divided injection controller 2 , and the control target is the injector 1 - 2 .

First, the split injection controller 2 performs the cold start determination control ( S10 ) in the engine system information detection step S11 , the first cold start condition determination step S12 , and the second cold start condition determination step S13 .

Referring to FIG. 2 , the split injection controller 2 inputs the coolant temperature and engine rotation speed among engine information detected by the engine ECU 10 when the engine 1-1 is started through CAN communication with the engine ECU 10 . It reads data and performs engine system information detection (S11).

Then, the divided injection controller 2 sequentially determines the first cold start condition to which the coolant temperature is applied (S12) and the second cold start condition to which the engine speed is applied (S13).

For example, the cooling water temperature determination formula is applied to the first cold start condition determination ( S12 ), and the engine rotation speed determination formula is applied to the second cold start condition determination ( S13 ).

Cooling water temperature determination formula: A < a ?

Engine speed determination formula: b-1 < B < b-2 ?

Here, “A” is the current coolant temperature detected after starting the engine, and “a” is a coolant temperature threshold that satisfies the first cold-start condition, and may be specified as 56°C between about 50 and 60°C. . Therefore, in determining the first cold start condition ( S12 ), the cooling water temperature value is applied as the determination condition. And “B” is the current engine speed detected after starting the engine, and “b-1” is an engine speed lower threshold that satisfies the second cold start condition, and can be specified as about 700 RPM, , “b-2” is an engine speed upper threshold that satisfies the second cold start condition, and may be specified as 960 RPM between about 900 and 1000 RPM. Therefore, determining the second cold start condition ( S13) applies the engine speed range as a judgment condition, and “<” is an inequality sign indicating the relationship between the two values.

As a result, the split injection controller 2 returns the engine system of S11 when the condition of “A < a” is not satisfied or the condition of “b-1 < B < b-2” is not satisfied when the condition of “A < a” is met. It returns to the information detection step and retrys the cold start determination, but if necessary, it may be switched to fuel injection control instead of cold start split injection control.

On the other hand, in the split injection controller 2, the engine speed (B) at a coolant temperature (A) lower than the coolant temperature threshold (a) is a region between the upper/lower limit thresholds (b-2, b-1) of the engine speed. When it is determined that the cold start state is in the cold start state by simultaneously satisfying the first and second cold start conditions, the cold start split injection control ( S20 ) is entered.

Then, the split injection controller 2 sets the cold-start split injection control (S20) so that the three-time homogeneous injection rule is satisfied by the injection sen mode control of S30, and the injection failure diagnosis control of S40 to the injection sen mode control (S30) In order to ensure that the mandatory breakdown diagnosis requirements for the system are satisfied, the final failure determination for the cold start split injection is made through the split injection monitoring of S50.

Therefore, the split injection controller 2 terminates the cold start split injection control when the injection failure diagnosis control (S40) confirms that the injectsen mode control (S30) is normal. After cold start, the split injection control is terminated.

Specifically, the injecten mode control ( S30 ) includes the first injecten mode performing step of S30-1, the second injecten mode performing step of S30-2, the third injecten mode performing step of S30-3, and S30-4 It is implemented in the step of generating the detection value of the injectsen motion.

In this case, the execution of the injecten mode control (S30) is performed in the first injecten mode (S30-1), and after determining the completion of the first injecten mode (S30-1), the second injecten mode (S30) -2), and after determining that the execution of the second injecten mode (S30-2) has been completed, the third injecten mode (S30-3) is performed and completed. Finally, the completion state of the third injecten mode (S30-3) leads to the step of generating an injecten motion detection value (S30-4), and the step (S30-4) of generating the injectionsen motion detection value is the first and second steps ,3 Gathers the measurement results of the injectsen mode (S30-1, S30-2, S30-2).

For example, the first injecten mode ( S30 - 1 ) is a primary (ie, first) cold start split injection. From this, the divided injection controller 2 measures the opening time and opening angle of the first injector by the operating current inflection point (eg, the Low Side in FIG. 2) after one injection of the injector 1-2, and the operating voltage inflection point (eg, 2) by measuring the closing time and closing angle of the primary injector, calculating the difference between the closing time of the primary injector and the opening time of the primary injector as the primary injector operating time, and counting the number of injector operations By assigning 1, the first injectsen mode (S30-1) is terminated.

For example, the second injecten mode ( S30 - 2 ) is a secondary (ie, second) cold start split injection following the end of the first injecten mode ( S30 - 1 ). From this, the divided injection controller 2 measures the opening time and opening angle of the secondary injector by the operating current inflection point (eg, the Low Side in FIG. 2) after the injection of the injector 1-2 twice, and the operating voltage inflection point (eg, 2) by measuring the closing time and closing angle of the secondary injector, and calculating the difference between the closing time of the secondary injector and the opening time of the secondary injector as the secondary injector operating time, and counting the number of injector operations By increasing 1 (that is, 2 = the number of operations (1)+1), the second injecten mode (S30-2) is terminated.

For example, the third injecten mode ( S30 - 3 ) is a third (ie, third) cold start split injection that follows after the end of the second injecten mode ( S30 - 2 ). From this, the divided injection controller 2 measures the opening time and opening angle of the 3rd injector by the operating current inflection point (eg, the Low Side in FIG. 2) after three injections of the injector 1-2, and the operating voltage inflection point (eg, The 3rd injector closing time and closing angle are measured by the Low Side of FIG. 2), and the difference between the 3rd injector closing time and the 3rd injector opening time is calculated as the 3rd injector operating time, and then counted for the number of injector operations By increasing 1 (that is, 3 = the number of operations (2)+1), the third injecten mode (S30-3) is terminated.

As an example, the injector operation detection value generation (S30-4) includes the injector opening angle, the injector closing angle, the injector operating time, and the number of injector operation in the first, second, and third injector modes (S30-1, S30-2, S30-1, S30-2, It is obtained from the execution result of S30-3).

Referring to FIG. 3 , the injection injection diagram illustrates the operating states of the injectors 1-2 with respect to the number of injections, the injector open, the injector close, and the injection start angle.

For example, the number of injections is determined by measuring the injection time between the injection start and the injection end. Therefore, each of the first, second, and third injector modes S30-1, 30-2, and 30-2 calculates the corresponding cylinder injection time of the injector 1-2 for each cylinder 1-1A when performing the operation. Measured and defined as the number of injections 1, 2, and 3 for the “Three Homogeneous Injection Rule” of the North American AECD dossier.

As an example, the injector opening is determined by measuring the inflection point occurrence point [②] after the injector operating current is applied, and the injector closing is determined by measuring the inflection point occurrence point [③] during the voltage value reduction after the injector is opened, and the injection start angle is between the start of the injector and the top dead center of the cylinder. It is determined by measuring.

Referring to FIG. 4 , the divided injection controller 2 includes an injector operation measurement unit 3 and an injector operation detection unit 4 .

As an example, the injector operation measurement unit 3 includes an injector open determination unit 3-1 that detects an operating current inflection point in the injector operating current flowing on the low side of the injector 1-2, and the low level of the injector 1-2. It is divided into an injector close determination unit (3-2) that detects the operating voltage inflection point in the injector operating voltage flowing on the side. Therefore, the injector open determining unit 3-1 performs first, second, and third injector opening times and opening angle measurements, and the injector closing determining unit 3-2 determines the first, second, and third injector closing times and opening angles. Perform closing angle measurement.

For example, the injector operation detecting unit 4 generates an injector opening angle, an injector closing angle, an injector operation time, and the number of injector operation as the injector operation detection values. In this case, the injector opening angle is obtained as an average value or an optimal value of the injector opening angles measured in the 1st, 2nd, and 3rd order, and the injector closing angle is obtained as the average value of the injector closing angles measured in the 1st, 2nd, and 3rd order or is obtained as an optimal value, wherein the injector operating time is obtained as an average value of the first, second, and third calculated injector operating times, or is obtained as an optimal value, or is obtained as a final value, 3rd injector operating time, the injector The number of operation is obtained as the number of injections through the measurement of the corresponding cylinder injection time for each cylinder, or is obtained as the accumulated number of counts of the 1st, 2nd, and 3rd cold start split injections.

Referring back to FIG. 1 , the injection failure diagnosis control ( S40 ) is performed in the step of checking the target injecten operation value of S40-1 and the step of diagnosing the injection failure of S40-2.

Referring to FIG. 4 , the divided injection controller 2 further includes a cold start divided injection determining unit 6 connected to the injector operation detecting unit 4 together with the injector operation target unit 5 .

For example, the injector operation target unit 5 provides the target injector opening angle, the target injector closing angle, the target injector operating time, and the target injector operation frequency to the cold start divided injection determining unit 6 .

Therefore, the check of the target injector operation value (S40-1) is performed by reading the target injector opening angle and time of S41, reading the target injector closing angle and time of S42, reading the target injector operating time of S43, and reading the target injector operation number of S44 is carried out

For example, the cold-start split injection determining unit 6 uses the injector opening angle, the injector closing angle, the injector operating time and the number of injector operations provided by the injector operation detection unit 4 as operating values, and the injector operation target unit 5 The target injector operating time, target injector opening angle, and target injector operating frequency among target injector opening angle, target injector opening time, target injector closing angle, target injector closing time, target injector operating time, and target injector operating frequency provided by and diagnose the injection failure using the operation value and the verification value.

To this end, the injection failure diagnosis (S40-2) is performed in the step of determining the injector operation time of S45, the step of determining the opening angle of the injector of S46, and the step of checking the number of times of operation of the injector of S47.

For example, the injector operation time determination (S45) applies the following operation time verification equation, and the injector opening angle determination (S46) applies an opening angle verification expression.

Operating time verification formula: |(D-d)/D| < x ?

Opening angle verification formula: |(E-e)/E| < y ?

Here, “D” is the target injector operating time, “d” is the injector operating time, and “|(Dd)/D|” is the difference between the target injector operating time and the injector operating time (Dd). is a dimensionless Time Index Estimation Value divided by , “x” is a dimensionless Time Index Threshold, about 0.2 is applied, and “E” is the target injector opening angle , “e” is the injector opening angle, and “|(Ee)/E|” is the dimensionless angle index calculation value (Angle) obtained by dividing the difference (Dd) between the target injector opening angle and the injector opening angle by the target injector opening angle. Index Estimation Value), and “y” is a dimensionless Angle Index Threshold of about 0.2. In addition, ”||“ is an absolute value, “-“ is a minus sign, ”/“ is a symbol for division, and “<“ is an inequality sign indicating a relationship between two values.

As a result, the divided injection controller 2 returns the first and second ,3 After judging that the operating time applied to the injection sen mode (S30-1, S30-2, S30-3) is normal, the injector opening angle determination (S46) is entered. Injector opening angle (E) - Injector opening angle (e))/ Target injector opening angle (E)| After determining that the opening angle applied in S30-3) is normal, the operation proceeds to check the number of injector operations (S47).

For example, the check of the number of operation of the injector (S47) applies the following operation number confirmation formula.

Number of operation confirmation formula: Number of operation of injector = k

Here, “number of injector operation” is the number of injector operations confirmed in the first, second, and third injector modes (S30-1, S30-2, S30-3), “k” is the target number of injector operation, and ”= “ is an inequality sign indicating that two values are equal.

As a result, when the number of injector operation and the target injector operation number are the same as 3, the divided injection controller 2 indicates that the first, second, and third injector modes (S30-1, S30-2, S30-3) were all normally performed. After the determination, the procedure of the divided injection control (S20) during cold start is terminated.

Referring back to FIG. 1, the divided injection monitoring (S50) is the result of the injection failure diagnosis (S40-2) of the injector operation time determination (S45), the injector opening angle determination (S46), and the injector operation count check (S47) is monitored, and as a result of the monitoring, a failure determination is made for the cold start split injection control (S20).

As an example, the divided injection controller 2, through the divided injection monitoring (S50), “|(target injector operating time (D) - injector operating time (d))/ target injector operating time (D)|< 0.2(x) A failure determination is made for the 1st, 2nd, and 3rd injecten modes (S30-1, S30-2, S30-3) by setting the operating time for which " is not satisfied, and |(target injector opening angle (E)- Injector opening angle (e))/target injector opening angle (E)| -3), and if the number of injector operation and the target injector operation number do not match 3 After judging the failure, the procedure of split injection control (S20) during cold start is terminated.

Referring to FIG. 4 , the divided injection controller 2 includes a failure determination unit 7 associated with the cold start divided injection determination unit 6 .

For example, the failure determination unit 7 generates an injection failure signal for the failure determination output from the cold start division injection determination unit 6, and the injection failure signal is a warning message to the driver. -6) is turned on.

Meanwhile, FIGS. 5 to 7 specifically exemplify an injecten mode procedure applied to each of the 1, 2, and 3 injecten mode control ( S30 ). In this case, in the injecten mode procedure, if the injecten operation detection value generation ( S30 - 4 ) can be obtained in the same way, some omissions, partial order changes, or some order integration may be made.

5, the first injector mode (S30-1) is an injector operating current and operating voltage detection step according to the fuel injection start of S31-1, an operating current inflection point determination step in the injector operating current of S32-1, Injector opening time measurement step in S33-1, injector opening angle measurement step in S34-1, operating voltage inflection point determination step at the injector operating voltage in S35-1, injector closing time measurement step according to the end of fuel injection in S36-1, S37 Injector closing angle measurement step according to the end of fuel injection in -1, injector operation time calculation step using the difference between injector closing time and injector opening time in S38-1, and checking the number of injector operation by counting in S39-1 do.

Referring to Figure 6, the second injector mode (S30-2) is the injector operating current and operating voltage detection step according to the fuel injection start of S31-2, the operating current inflection point determination step in the injector operating current of S32-2, Injector opening time measurement step S33-2, injector opening angle measurement step S34-2, operating voltage inflection point determination step at the injector operating voltage in S35-2, injector closing point measurement step according to the end of fuel injection in S36-2, S37 -2, the step of measuring the closing angle of the injector according to the end of fuel injection, the calculating of the injector operating time using the difference between the closing time of the injector and the opening time of the injector of S38-2, and the step of checking the number of times of injector operation by increasing the count of S39-2 do.

Referring to FIG. 7 , the third injector mode (S30-3) is a step of detecting an injector operating current and an operating voltage according to the start of fuel injection in S31-3, a step of determining an operating current inflection point in the injector operating current of S32-3, S33-3 measuring the injector opening time, S34-3 measuring the injector opening angle, S35-3 determining the operating voltage inflection point at the injector operating voltage, S36-3 measuring the injector closing time according to the end of fuel injection, S37 -3 step of measuring the closing angle of the injector according to the end of fuel injection, calculating the injector operating time using the difference between the closing point of the injector and the opening point of the injector of S38-3, and the step of checking the number of injector operation by increasing the count of S39-3 do.

As described above, the injecten mode procedure applied to each of the 1, 2, and 3 injectsen mode control (S30) is the injector opening angle, the injector closing angle, the injector closing angle, the injector operating time and the number of injector operation obtained from the result as an operating value. There is only a difference in the numerical values, but the overall steps are the same.

As described above, in the cold start split injection control method applied to the engine system 1 according to the present embodiment, the split injection controller 2 controls the injectors 1 - 2 according to the cold start operation of the engine system 1 . By performing cold-start split injection with a divided injection operation, any one or more of the injector opening angle, injector operating time, and injector operation count is measured as an operating value, and target injector opening angle, target injector closing angle, target injector operating time, target CARB OBD-2 section 1968.2 that stipulates 3 fuel injections by reading any one or more of the number of injector operation as a verification value and applying it to the failure determination for the cold start split injection, and North American AECD document that stipulates the cold start control failure diagnosis The requirements must be met together, and in particular, the expansion of the cold start area of the split injection control can preemptively respond to the strengthening of emission gas regulations.

1: engine system
1-1: cylinder block 1-1A: cylinder
1-2: injector 1-3: fuel rail
1-4: high pressure pump 1-5: fuel rail pressure sensor
1-6 : engine warning light
2: Split injection controller
3: Injector operation measurement unit 3-1: Injector open determination unit
3-2: Injector close judgment unit
4: injector operation detection unit 5: injector operation target unit
6: Cold start split injection judgment unit
7: Failure judgment unit
10: Engine ECU (Electronic Control Unit)

Claims (20)

Injectsen mode control step of performing the cold start split injection by the operation of the injector by the split injection controller that determines the cold start condition of the engine system;
Injection failure diagnosis control step of performing injection failure diagnosis with any one or more of the injector opening angle, injector operating time, and injector operation frequency measured through fuel injection of the injector
Cold start split injection control method, characterized in that it is included.
The method according to claim 1, wherein the cold start condition applies a coolant temperature and an engine speed, and the cold start condition is determined by considering the engine speed after considering the coolant temperature first. .
The method according to claim 2, wherein the cooling water temperature is applied as a judgment condition with a set cooling water temperature of 56°C.
The method according to claim 2, wherein the engine speed is applied as a determination condition in a set engine speed range of 700 to 960 RPM (Revolution Per Minute).
The method according to claim 1, wherein the injector mode control performs the cold start split injection to generate any one or more of an injector opening angle, an injector closing angle, an injector operation time, and the number of injector operation as an injector operation detection value. Cold start split injection control method with
The method according to claim 5, wherein the injector mode control comprises the steps of determining the operating current inflection point by detecting the injector operating current according to the start of fuel injection, measuring the opening time of the injector and measuring the opening angle of the injector, and operating the injector according to the start of fuel injection A step of determining the operating voltage inflection point by voltage detection, a step of measuring an injector closing time and an injector closing angle according to the end of fuel injection, a step of calculating an injector operating time, and a step of counting the number of injector operations
A cold start split injection control method, characterized in that it is performed as
The method according to claim 6, wherein the injector operating time is calculated as a difference between a closing time of the injector and an opening time of the injector.
The cold-start split injection control according to claim 6, wherein the injecten mode control is performed in the first injecten mode, the second injecten mode, and the third injecten mode in which the number of times of injector operation is increased by one count. method.
The method according to claim 1, wherein the injection failure diagnosis control comprises: identifying a target injector opening angle, a target injector closing angle, a target injector operating time, and a target injector operating time; a step of making a time verification determination for the injector opening angle and an angle verification determination of the injector opening angle with the injector opening angle and the target injector opening angle; Steps in which this takes place
A cold start split injection control method, characterized in that it is performed as
The method according to claim 9, wherein the time verification determination includes a time index calculation value obtained by dividing the difference between the target injector operating time and the injector operating time by the target injector operating time and a Time Index Threshold ) cold start split injection control method, characterized in that it is applied.
The method according to claim 10, wherein the time index threshold is 0.2.
The method according to claim 10, wherein the cold start divided injection is determined to be faulty when the calculated time index is less than the time index threshold value.
The method according to claim 9, wherein the angle verification determination comprises an angle index calculated value obtained by dividing the difference between the target injector opening angle and the injector opening angle by the target injector opening angle and an angle index threshold value. ) cold start split injection control method, characterized in that it is applied.
The method according to claim 13, wherein the angle index threshold is 0.2.
The method according to claim 13, wherein the cold start divided injection is determined to be faulty when the calculated value of the angle index is less than the threshold value of the angle index.
The method according to claim 9, wherein the same numerical value is applied to the target injector operation frequency and the injector operation frequency to check the number of times, and when the numerical values do not match, the cold start divided injection is determined to be faulty.
The method according to claim 16, wherein the numerical equality is three.
According to the cold-start operation, cold-start split injection is performed with three divided injection motions of the injector, and any one or more of the injector opening angle, the injector operating time, and the number of injector operation is measured as the operating value, and the target injector opening angle and the target injector closing a split injection controller that reads at least one of an angle, a target injector operation time, and a target injector operation frequency as a verification value and applies it to a failure determination for the cold-start split injection; and
An engine warning light that warns of the failure determination under the control of the split injection controller
Engine system, characterized in that it is included.
The engine system according to claim 18, wherein the divided injection controller determines the condition of the cold start operation based on at least one of a set coolant temperature applied to the coolant temperature and a set engine speed range applied to the engine speed.
19. The method according to claim 18, wherein the divided injection controller comprises an injector open determining unit detecting an operating current inflection point of the injector, an injector closing determining unit detecting an operating voltage inflection point of the injector, an injector operation detecting unit generating the operating value, and the verification The operation value and the verification value are applied to any one of an injector operation target unit that generates a value, a time verification determination for the injector operating time, an angle verification determination for the injector opening angle, and a number verification for the number of operation of the injector A cold start split injection determination unit that performs the failure determination and a failure determination unit that outputs a signal for the failure determination
Engine system, characterized in that consisting of.

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